Red azo dye for lakes and process of making same.



WILHELM KfiNIG, OF OHRDRUF, GERMANY.

RED AZO DYE FOR LAKES AND PROCESS MAKING SAME.

No Drawing.

To all whom it may concern: I

Be it known that I, \VILIIELM KGNIG, doctor of philosophy, chemist, asubject of the Emperor of Germany, residing at Ohrdruf, in the Duchy ofSaxe-Coburg-Gotha, Germany, have invented new and useful Improvements inRed Monoazo Dyestuffs Specially Valuable for the Preparation of PigmentColors Entirely Insoluble in Oil, of which the following is aspecification.

So far as I am aware, all the igment colors insoluble in oil preparedhitherto from coal-tar colors contain one or more sulfo groups in themolecule. Colors which cont ain a carboxylic group obtained by combininga-nilin carboxylic acids, diazotized with beta-naphthol, are veryreadily soluble in oil, and compounds of anilin and its indifferentderivatives, diazotized with naphthol carboxylic acids, especially2.3-oxynaphthoic acid, are also soluble in oil. I have discovered that,contrary to expectation, dye stuffs produced by combining anilincarboxylic acids diazotized with 2.3-oxynaphthoic acid (havinga meltingpoint of 216 degrees centigrade) will yield pigment colors which are inthe form of metallic salts and which are completely insoluble in oil.

The new dyestuffs are of the general formula:

0 X,.oooH.N .c u .on.oooH,

wherein X means hydrogen atoms or Cl, Br, 1, alkyl groups, alkyloxygroups, N0 and other indifferent substitutes in any number andstructural arrangement within the moleoule.

The following shows how these new coloring matters may be produced. Theparts are by weight.

Example: 17.15 parts of chloranilin carboxylic acid (NH,:G1:COOH 1:225)are dissolved in 17 parts of hydrochloric acid 20 Baum diluted beforewith 500 parts of water. This solution is cooled down to 5 centigrade byaddition of ice and thereupon diazotized by adding slowly 69 parts ofsodium nitrate. The diazo solution thus obtained is then poured into acold solution of 19 parts of 2.3-oxynapththoic acid (having a meltingpoint of 216 0.) in 33.5 parts of Specification of Letters Patent.

Patented Dec. 14, 1909.

Application filed September 12, 1907. Serial No. 392,466.

caustic soda lye 36 Baum previously diluted with 200 parts of water andmixed with a solution of 5.5 parts of calcined soda. After thecombination is completed the dyestnfl' is precipitated by addition ofcommon salt-and then filtered in the usual manner.

F or preparing pigment colors the dyestufi' may be employed in the formof a paste or in the form of a powder. The solution or the paste of thesodium salts first formed is mixed in the usual manner with solutions ofmetal salts, for instance of barium chlorid, calcium chlorid, nitrate oflead and others and then stirred at a lower or higher temperature forthe purpose of mutual decom position. The nature of the substratum orbody may be accommodated to the intended application of the pigmentcolor, so for instance highly ground native sulfate of barium may beemployed for painting colors, whereas aluminum-hydroxid may be employedfor printing inks.

The following table gives some of the properties of the pigment colorsobtained according to this invention:

Colors prepared by the combination of dmzouzed Gives pigment colorspchloranilin m- CalbOX- ylic acid An i i n m e t a carboxylic Pure bluered (Ca-salt.)

ac Pure blue red (CasaltJ Anildi n p are carboxylic All these pigmentcolors are of an excellent fastness to light and quite insoluble inwater, oil and alcohol.

Having thus described my invention, what. I claim and desire to secureby Letters Patent, is-

1. The herein described process of mamr facturlng monoazo dyestuffsespecially adapted for preparing red pigment colors insoluble in oil,consisting in causing 2.3- oxynaphthoic acid (having a melting pointof216 C.) to react with diazotized anilin carboxylic acids of the generalformula.

: tained by JC X NH OOOH, wherein means hydrogen atoms or Cl, Br, I,alkyl groups, oxalkyl groups, NO and other indifl'erent substitutes. 2.As anew product the dyestuffs obcombining the diazotized anilincarboxylic acids of the general formula C X,.NH .COOH, wherein X meanshydrogen atoms or Cl, Br, I, alkyl groups, alkoxy groups, NO and otherindifferent substitutes with 2.3-oxynaphthoic acid having a meltingpointof 216 C. forming red pastes or red powders soluble in water to ared solution and soluble in concentrated sulfuric acid to a blue redsolution from which ,the red brown free acids of the dyestuifs may beprecipitated. I

3. As a new product of manufacture, the pigment colors prepared bymixing the paste or the solution of dyestufis of the general formula C X.COOH.N .C H,.OH. COOH;

wherein X means hydrogen atoms or Cl, Br,

I, alkyl groups, alkoxy grou s, NO and other different substitutes, witsolutions of metal salts, the. pigment colors so obtained 7 beingcompletely insoluble in water, oil and alcohol and of an excellentresistance to In testimony whereof, I have signed my name to thisspecification, in the presence of two subscribing Witnesses.

WILHELM KONIG.

Witnesses:

W. Fox BRUCE, FR. STENGEL.

